1. Field of the Invention
One embodiment of the present invention relates to a lighting device including a light-emitting material exhibiting electroluminescence.
2. Description of the Related Art
A lighting device in which a light-emitting element containing an electroluminescent material is used has higher emission efficiency than incandescent lamps or fluorescent lamps, and therefore has attracted attention as a next-generation lighting device. A light-emitting element containing an electroluminescent material can be formed in the form of a thin film with a thickness of 1 μm or less by a method such as an evaporation method or a coating method. A lighting device with a modified mode has been reported (e.g., Patent Document 1).    [Patent Document 1] Japanese Published Patent Application No. 2005-332773